RU2757390C2 - Preparation of n,n-(di)alkylaminoalkyl(meth)acrylamide or n,n-(di)alkylaminoalkyl(meth)acrylate and their quaternary ammonium salts as flocculating auxiliary substances and gel-forming agents - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to a method for the preparation of N,N-(di)alkylaminoalkyl(meth)acrylamide or N,N-(di)alkylaminoalkyl(meth)acrylate or their quaternary ammonium salts. The specified method includes interaction in a liquid phase of alkyl(meth)acrylate with amine or alcohol to obtain a product containing the specified N,N-(di)alkylaminoalkyl(meth)acrylamide or N,N-(di)alkylaminoalkyl(meth)acrylate or their quaternary ammonium salts, wherein the concentration of oxygen in the liquid phase is <1000 ppm, and the specified N,N-(di)alkylaminoalkyl(meth)acrylamide or N,N-(di)alkylaminoalkyl(meth)acrylate have the formula (I), in which R₀ is hydrogen or methyl, X is NH or O, R₂ is linear branched or cyclic alkylene radical containing 1-12 carbon atoms or aryl radical, which can also be substituted with at least one alkyl group, R₃, R₄ are linear branched or cyclic alkyl radical containing 1-12 carbon atoms or aryl radical, which can also be substituted with at least one alkyl group. The product has the content of less than 1200 ppm of a compound of the formula (IV), in which R₀ is hydrogen or methyl, X is NH or O, R₅ in each case is linear branched or cyclic alkylene radical, aryl radical, which can also be substituted with at least one alkyl group, linear, cyclic or branched alkyl radical containing 1-12 carbon atoms.

EFFECT: proposed method allows obtaining N,N-(di)alkylaminoalkyl(meth)acrylamides or N,N-(di)alkylaminoalkyl(meth)acrylates with low content of compounds of the formula (IV).

10 cl, 2 tbl, 4 ex

Description

The present invention relates to a process for the preparation of N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate and their quaternary ammonium salts having a low content of compounds corresponding to formula (IV).

The preparation of dimethylaminopropyl methacrylamide (DMAPMA) is known from the prior art.

EP 0960877 (Elf Atochem S.A.) describes a continuous process for the preparation of dialkyl amino alcohol methacrylate esters. Dialkylamino alcohols are typically reacted with methyl (meth) acrylate and the dialkylaminoalkyl (meth) acrylate is prepared as follows.

A mixture of starting materials (methyl (meth) acrylate and dialkylamino alcohol) with stirring is continuously charged into the reactor together with a tetraalkyl titanate used as a catalyst (for example, tetrabutyl, tetraethyl or tetra (2-ethylhexyl) titanate), and with at least one a polymerization inhibitor (for example, phenothiazine, tert-butylcatechol, hydroquinone monomethyl ether or hydroquinone), where the conversion to obtain dialkylamino (meth) acrylate is carried out at a temperature of 90 ° C-120 ° C, while continuously removing the methyl (meth) azeotropic mixture acrylate / methanol. The crude reaction mixture (crude ester) is charged to the first distillation column, where the substantially catalyst-free stream is discharged at the top of the distillation column under reduced pressure, and the catalyst and a small amount of dialkylaminoalkyl (meth) acrylate are discharged at the bottom of the distillation column. The overhead stream leaving the first distillation column is then charged to a second distillation column, in which, under reduced pressure, a stream containing low boiling point products and a small amount of dialkylaminoalkyl (meth) acrylate is discharged at the top and a stream mainly containing dialkylaminoalkyl (meth) acrylate and the polymerization inhibitor (s) are discharged at the bottom and charged to the third distillation column. In the third distillation column under reduced pressure, distillation is carried out, in which the desired pure dialkylaminoalkyl (meth) acrylate is discharged at the top and a stream mainly containing the polymerization inhibitor (s) is discharged at the bottom. After further purification with a film evaporator, the bottom stream leaving the first distillation column and the overhead stream leaving the second distillation column are returned to the reactor.

This method does not carry out dehydration of alcohols before their use, which can lead to increased deactivation of the tetraalkyl titanate used due to hydrolysis, which proceeds while unwanted solid deposits are formed. In addition, the method has the disadvantage that the catalyst is subjected to heat stress at relatively high temperatures at the bottom of the first distillation column. This can easily lead to the destruction of the catalyst.

In this method, only two head rectifications are carried out, in both, unreacted reagents and the product are separated. This leads to high energy costs and the need to use only 4 rectification columns, some of which are extremely large. Therefore, the disadvantages of the method are very high capital and operating costs.

EP 0968995 (Mitsubishi Gas Chemical Comp.) Describes a continuous process for producing alkyl (meth) acrylates using a reaction column. In this case, the transesterification reaction is carried out directly in the distillation column (i.e., the reactor and the distillation column designed to remove the methyl (meth) acrylate / methanol azeotrope are part of one apparatus), into which the starting materials (methyl (meth ) acrylate and alcohol). The required catalyst, in this case also preferably a titanium compound, is contained in the distillation column. In the case of using a homogeneous catalyst, the catalyst is continuously metered into the distillation column. However, the use of a homogeneous catalyst in the distillation column results in an increase in the required amount of catalyst due to the washout effect resulting from the outflow of liquid in the distillation column and contamination of the inside of the column if the solid catalyst is precipitated. In the case of using a heterogeneous catalyst, the catalyst is in the reaction column. However, placing the catalyst in the distillation column has the disadvantage that an overpressure then drops in the distillation column, and furthermore, regular cleaning of the distillation column is extremely costly and difficult. In addition, deactivation of heterogeneous catalysts can occur, for example, as a result of an undesirable polymerization reaction.

GmbH) описан проводимый в непрерывном режиме способ получения алкиламино(мет)акриламидов путем проводимого в непрерывном режиме аминолиза. В этом случае уменьшение содержания сшивающего реагента обеспечивают с помощью сложных стадий обработки, предпочтительно перегонки.In US 8674133 (Evonik

GmbH) describes a continuous process for the production of alkylamino (meth) acrylamides by continuous aminolysis. In this case, the reduction in the content of the crosslinking agent is achieved by complex processing steps, preferably distillation.

The methods described above lead to the formation of various by-products, most of which should not be contained in the final product. Known disadvantages associated with the removal of by-products are, for example, reduced yields and increased capital, operating and maintenance costs resulting from the need for purification steps.

In the synthesis of N, N- (di) alkylaminopropyl methacrylamides and their quaternary ammonium salts, the formation of compounds of formula (IV) is particularly undesirable.

The increased content of this compound in the final product leads to premature and uncontrolled crosslinking during polymerization.

The objective of the present invention was to develop a method by which it is possible to obtain N, N- (di) alkylaminoalkyl (meth) acrylamides or N, N- (di) alkylaminoalkyl (meth) acrylate and their quaternary ammonium salts having a low content of compounds of the formula (IV ). Another object of the present invention was to provide a process for the preparation of monomers that provide soluble or non-coagulable polymers.

The problem was solved using a method for producing N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate of general formula (I),

wherein

R ⁰ denotes hydrogen or methyl,

X stands for NH or O,

R ₂ , R ₃ , R ₄ all denote a linear, branched or cyclic alkyl radical, an aryl radical, which can also be substituted by one or more alkyl groups, a linear, branched or cyclic alkyl radical can contain 1-12 carbon atoms and is e.g. methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, hexyl, heptyl, octyl, isooctyl, nonyl, decyl, undecyl, dodecyl, containing less than 1200 ppm. compounds of general formula (IV),

in which R ₅ in each case denotes a linear, branched or cyclic alkyl radical, an aryl radical, which can also be substituted by one or more alkyl groups, a linear, branched or cyclic alkyl radical can contain 1-12 carbon atoms and is, for example , methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, hexyl, heptyl, octyl, isooctyl, nonyl, decyl, undecyl, dodecyl, characterized in that the oxygen concentration in the liquid phase at the stage of production is at least one component is <1000 ppm

The problem was solved using a method for preparing N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate of general formula (I) and their quaternary ammonium salts containing compounds of formula (IV), constituting less than 1200 ppm, characterized in that it is carried out at a reduced oxygen content.

Preferably, the content of the compounds of formula (IV) is less than 1000 ppm, more preferably less than 850 ppm, most preferably less than 700 ppm.

In the present invention, the term "(meth) acrylate" means both methacrylate, for example, methyl methacrylate, ethyl methacrylate, and the like, and an acrylate, for example, methyl acrylate, ethyl acrylate and the like, and mixtures of both.

The problem is also solved using the method corresponding to paragraph 1 of the formula of the invention a method of obtaining N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate or their quaternary ammonium salts containing a compound of the formula (IV) less than 1200 ppm, which are used to obtain soluble or non-coagulating polymers.

In this context, the preparation of soluble or non-coagulable polymers means that N, N- (di) alkylaminoalkyl (meth) acrylamides or N, N- (di) alkylaminoalkyl (meth) acrylates obtained in accordance with the present invention, after polymerization or copolymerization with others compounds, can be dissolved in a suitable solvent or obtained from them a non-coagulating emulsion or dispersion. Similarly, N, N- (di) alkylaminoalkyl (meth) acrylamides or N, N- (di) alkylaminoalkyl (meth) acrylates quaternized in accordance with the present invention, after polymerization or copolymerization, can be dissolved in suitable solvents.

According to the invention, it has surprisingly been found that the amount of compounds of formula (IV) formed can be minimized by reducing the oxygen concentration in the reaction system.

A decrease in the oxygen concentration means that in the preparation of N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate, the oxygen concentration in the liquid phase at the stage of obtaining at least one component is <1000 h ./million Preferably, when converting the reactants in a reaction vessel or in a cascade of stirred tanks, the oxygen concentration in the liquid phase is less than 1000 ppm.

Ideally, the reaction is carried out in the absence of oxygen. The reaction can be carried out in a vacuum or in an atmosphere of protective gas, for example, under an atmosphere of N ₂ or argon.

It has been found according to the invention that a decrease in residence time can also help to reduce the amount of compounds of formula (IV) formed. Reducing the residence time without significantly reducing the yield of the product per pass per unit of time can be achieved by taking the following measures:

- the use of catalysts with higher activity,

- the use of an increased amount of catalyst,

- displacement of equilibrium as a result of removal of an increased amount of alcohol, for example, by using columns with a larger capacity and / or supplying more energy.

According to the invention, it has surprisingly been found that a decrease in the reaction temperature also leads to a decrease in the content of the compounds of the formula (IV). To prevent heating to high temperatures, which is common in the process at the end of the reaction, the pressure is reduced at the same time. Preferably, the pressure drop during the reaction is provided at the end of the reaction. Accordingly, at the beginning of the reaction, the pressure can also be increased.

The method of obtaining N, N- (di) alkylaminoalkyl (meth) acrylamides or N, N- (di) alkylaminoalkyl (meth) acrylate includes aminolysis or alcoholysis of alkyl (meth) acrylates using amines or alcohols with the release of alcohols.

The starting reagent, (meth) acrylate, is continuously fed to a suitable reaction apparatus, whereby either one reaction vessel or a cascade consisting of two or more reaction vessels connected in series can be used. Such a cascade can consist, for example, of 2, 3, 4, 5, 6 or optionally more reaction vessels. In a preferred embodiment, a cascade of 3 continuous stirred tanks connected in series is used.

The feed of the starting reagent, (meth) acrylate, can be done in different ways. For example, the reactant stream can be supplied only to the first reaction vessel of the cascade, or the reactant stream can be divided into substreams and these substreams can be supplied to all or only some of the series-connected reaction vessels of the cascade. Likewise, the reactant stream can be fed to a distillation column for separating low boiling point compounds and / or to reaction apparatus. It may be preferable to feed the reactant stream only to a distillation column for separating low boiling compounds, or, in another embodiment, separating the reactant stream into substreams that are then fed either to a distillation column for separating low boiling compounds, or to the first, or optionally into two or more reaction vessels that make up the cascade.

Suitable alkyl (meth) acrylates are compounds of formula (II),

wherein

R ₀ denotes hydrogen or methyl,

R ₁ denotes a linear or branched alkyl radical containing from 1 to 10, preferably from 1 to 4 carbon atoms.

Typical examples of these compounds are methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, 3-methylbutyl (meth) acrylate , amyl (meth) acrylate, neopentyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, heptyl (meth) acrylate, n-octyl (meth) acrylate, ethylhexyl (meth) acrylate or decyl (meth) acrylate ...

Preferably, all of the reaction vessels include a device for drawing steam into a distillation column to remove alcohol liberated during the reaction.

It has been found that in preferred embodiments it is preferable to provide an outlet from one tank of the cascade to the bottom of the next tank of the cascade, in each case located downstream.

The reagent is continuously fed to a distillation column designed to separate low-boiling compounds for dehydration.

Suitable reagents are compounds of formula (III),

wherein

X = OH or NH ₂

R ₂ , R ₃ , R ₄ all denote a linear, branched or cyclic alkyl radical, an aryl radical, which can also be substituted by one or more alkyl groups, a linear, branched or cyclic alkyl radical can contain 1-12 carbon atoms and is for example methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, hexyl, heptyl, octyl, isooctyl, nonyl, decyl, undecyl, dodecyl.

Examples of suitable reactants include the following compounds: dimethylaminoethylamine, diethylaminoethylamine, dipropilaminoetilamin, diizopropilaminoetilamin, dibutilaminoetilamin, diizobutilaminoetilamin, dimethylaminopropylamine, diethylaminopropylamine, dipropilaminopropilamin, diizopropilaminopropilamin, dibutilaminopropilamin, diizobutilaminopropilamin, dimethylaminobutylamine, dietilaminobutilamin, dipropilaminobutilamin, diizopropilaminobutilamin, dibutilaminobutilamin, diizobutilaminobutilamin, dimetilaminogeksilamin, dietilaminogeksilamin, dimetilaminoneopentilamin, metiletilaminopropilamin , metilpropilaminopropilamin, metilpropilaminoetilamin, metiletilaminoetilamin, dimethylaminoethyl alcohol, diethylaminoethyl alcohol dipropilaminoetilovy alcohol diizopropilaminoetilovy alcohol dibutilaminoetilovy alcohol diizobutilaminoetilovy alcohol dimetilaminopropilovy alcohol dietilaminopropilovy alcohol dipropilaminopropilovy alcohol diizopropilaminopropilovy alcohol, alcohol dibutilaminopropilovy , Diizobutilaminopropilovy alcohol dimetilaminobutilovy alcohol dietilaminobutilovy alcohol dipropilaminobutilovy alcohol diizopropilaminobutilovy alcohol dibutilaminobutilovy alcohol diizobutilaminobutilovy alcohol dimetilaminogeksilovy alcohol dietilaminogeksilovy alcohol dimetilaminoneopentilovy alcohol metiletilaminopropilovy alcohol metilpropilaminopropilovy alcohol metilpropilaminoetilovy alcohol metiletilaminoetilovy alcohol.

Particularly preferred are dimethylaminopropylamine, dimethylaminoethylamine, dimethylaminohexylamine, dimethylaminopropyl alcohol, dimethylaminoethyl alcohol and dimethylaminohexyl alcohol.

Likewise, it is preferred if catalysts and polymerization inhibitors are continuously metered into the reaction apparatus.

The catalysts for the transesterification reaction can be any catalysts known in the art.

Useful catalysts include, for example, zirconium acetylacetonate and other complexes of 1,3-diketones with zirconium; in addition, it is possible to use mixtures of alkali metal cyanates or alkali metal thiocyanates with alkali metal halides, as well as tin compounds, for example, dioctyltin oxide, alkaline earth metal oxides or alkaline earth metal hydroxides, for example, LiOH, CaO, Ca (OH) ₂ , MgO, Mg (OH) ₂ , or mixtures of the above compounds, as well as alkali metal hydroxides, alkali metal alkoxides and lithium chloride and lithium hydroxide; you can also use mixtures of the above compounds with the above compounds of alkaline earth metals and lithium salts, in particular with lithium chloride and calcium hydroxide, dialkyltin oxides, for example, dioctyltin oxide, alkali metal carbonates, alkali metal carbonates together with quaternary ammonium salts, for example, with tetrabutylammonium hydroxide or hexadecyltrimethylammonium bromide, as well as mixed catalysts consisting of tin diorganoxide and tin organohalide, acidic ion exchange resins, phosphomolybdenum heteropolyacids, titanium alkoxides, for example, isopropyl titanate, chelates, zirconium or zirconium compounds such as titanium , lead compounds, for example, lead oxides, lead hydroxides, lead alkoxides, lead carbonates or lead salts with carboxylic acids, and alkaline earth metal amides, especially lithium amide. Likewise, alkali metal alkoxides are suitable, lithium alkoxides are preferred, and lithium methoxide is particularly preferred. Particularly preferred is a catalyst mixture comprising dialkyltin oxide and an alkyl titanate, for example dioctyltin oxide and isopropyl titanate, in a ratio of about 1: 3 (wt%) to 3: 1 (wt%). The mixture of catalysts is used in an amount of 0.1% -10 wt. % based on the amount of reagents used.

It has been found that pre-activation of the catalyst is preferred. It includes mixing or dispersing the catalysts, heating them to temperatures equal to 90 to 120 ° C, and stirring them for 2 to 3 hours until a homogeneous transparent solution is formed.

Examples of useful polymerization inhibitors include hydroquinone, hydroquinone monomethyl ether, and piperidyl derivatives.

Due to the decrease in oxygen concentration, it may be necessary to replace commonly used stabilizers that require oxygen with stabilizers that operate in the absence of oxygen.

Preferred are polymerization inhibitors selected from the group consisting of bis (2-methoxycarbonylpropyl) sulfide, N, N-diethylhydroxylamine, phenothiazine, 4-hydroxy-2,2,6,6-tetramethylpiperidinooxyl or N, N'-diphenyl-p-phenylenediamine and its derivatives (eg esters, amides, etc.).

It is especially preferred if the choice of starting materials is carried out in such a way that the equilibrium can be shifted towards the products by removing the alcohol from the reaction mixture. Removal of the alcohol can be carried out by distillation due to its lower boiling point compared to the boiling point of the reagents used and / or by obtaining an azeotropic mixture.

The reagent used may contain water. The amount of water contained in the used reagent is less than 5000 ppm. Before adding the reagent to the reaction apparatus, it is dewatered by distillation, preferably using a distillation column. This procedure involves removing the water contained in the reagent as an overhead stream. To avoid contamination of the low boiling point effluent stream with the reagent used, it is preferred if the reagent is introduced into the bottom of the distillation column. The reagent used can also be dehydrated in other ways:

- by using a distillation column for dewatering located before the entrance to the apparatus,

or

- by treatment with a dehydrogenating agent such as molecular sieves,

or

- by the method of membrane separation, for example, by evaporation through a permeable partition.

Dehydration is important because the water contained in the reactant can permanently damage the catalyst in the reactor. The water contained in the reagent can lead to the formation of by-products and therefore it is imperative to avoid its presence. This dewatering step avoids hydrolysis of the catalyst and the associated costs associated with using an increased amount of catalyst and due to the difficulties associated with solid precipitates. In addition, as the amount of by-products is reduced, the purity of the product increases.

The reaction is carried out in a reaction apparatus at a temperature ranging between 70 ° C and 160 ° C, in accordance with the system and the operating pressure.

In accordance with the present invention, the reaction temperature can be lowered to minimize the amount of compounds of formula (IV) formed. It is preferable if the temperature is lowered to 80-120 ° C, more preferably if the temperature is lowered to 80 to 90 ° C. Therefore, a reduced pressure is used to ensure maximum conversion. In continuous operation, it is preferable if the conversion is carried out in a cascade of tanks. All components of the cascade can be operated at reduced pressure; preferably, if the pressure is reduced in the last component of the cascade.

Preference is given to working under vacuum at a pressure of 900 to 0 bar.

In accordance with the present invention, a decrease in residence time can also lead to a decrease in the content of compounds of formula (IV) in the final product.

A residence time of 0.1 to 11 hours, preferably 1 to 5 hours, results in a marked reduction in the content of compounds of formula (IV) in the final product.

In order to achieve a sufficiently high conversion despite a reduced residence time, it is necessary to use more active catalysts or / and to increase the amount of catalyst.

To increase the reaction rate, the alcohol liberated during the reaction is removed from the reaction mixture using a distillation column, optionally also as an azeotropic mixture containing the alcohol. This can be done at atmospheric pressure or under reduced pressure.

After staying in the reactor for about 0.5-4 hours, preferably after staying in the reactor for 1-2 hours, the reaction mixture containing mainly the product, N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N - (di) alkylaminoalkyl (meth) acrylate, unreacted (meth) acrylate and reagent, and small amounts of alcohol, catalyst, polymerization inhibitors and some by-products are charged to a continuous falling film evaporator. The vapors leaving the falling film evaporator are charged to a distillation column for separating low boiling point compounds. In this column, under reduced pressure, preferably in the range of about 1-500 mbar, components that have a low boiling point with respect to the product are removed, mainly the alcohol product and the unreacted reactant (meth) acrylate and the reactant amine or alcohol. They are removed through the top of the distillation column and recycled to the reactor or distillation column. The use of this recycle stream provides a high conversion in terms of the amount of reactants and for the entire process.

It is preferable if the crude product, which still contains as impurities catalyst, polymerization inhibitor and high boiling point by-products, and which is obtained as a stream leaving the evaporator with a falling film contains> 80 wt. % of the product and for processing it is sent to an additional stage of distillation under vacuum, which is carried out at a pressure, preferably in the range from 0.1 to 200 mbar. In this case, the pure product is isolated in the form of a head product by distillation. Known apparatus suitable for this purpose are a falling film evaporator, a film evaporator, and a molecular evaporator.

After the preparation of N, N- (di) alkylaminoalkyl (meth) acrylamides or N, N- (di) alkylaminoalkyl (meth) acrylates, they can optionally be introduced into a downstream distillation unit for purification, which can also be operated under reduced pressure, for example , when equal to 500-0.1 mbar. This is especially necessary if a particularly careful removal of the high-boiling secondary components formed during the process is to be carried out.

N, N- (Di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate obtained in accordance with the present invention, having a low content of compounds of formula (IV), can be reacted with an alkyl halide or alkyl sulfonate preferably with methyl chloride to form the corresponding quaternary ammonium salt.

N, N- (Di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate and their quaternary ammonium salts having a low content of compounds of formula (IV) are particularly suitable for the preparation of polymers which dissolve or polymerized in solution or as an emulsion or dispersion.

N, N- (Di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate having a compound of formula (IV) of less than 1200 ppm, obtained in accordance with paragraph 1 of the formula The invention is preferably used for polymerization carried out as bulk polymerization, solution polymerization, dispersion polymerization or emulsion polymerization, and they find use as thickening agents, gelling agents, hair care compositions (conditioning polymers), fixatives for hair, hair styling polymers, film-forming agents used in the home, in industry and in institutions, cleaning agents, flocculants, water clarifiers, auxiliary substances / additives used in the manufacture of paper, printing ink, reagents for reducing hydraulic losses used in oil and gas industry, and as inhibitors of the formation of gas hydrates, etc.

Similarly, N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate having a compound of formula (IV) of less than 1200 ppm, prepared according to Claim 1 is preferably used for conversion to quaternary ammonium salts which are used for polymerization and which find use as thickeners, gelling agents, hair care compositions (conditioning polymers), hair fixatives, hair styling polymers , film formers used in the home, in industry and in institutions, cleaning agents, flocculants, water clarifiers, auxiliary substances / additives used in the manufacture of paper, printing inks, reagents for reducing hydraulic losses used in the oil and gas industry, and as inhibitors formation of gas hydrates, etc.

The method proposed in the present invention is explained in detail using the examples below, but it is not limited to them.

Examples of

Example 1

Synthesis of N, N-dimethylaminopropyl methacrylamide (DMAPMA) in the absence of oxygen

To obtain N, N-dimethylaminopropyl methacrylamide in a continuous mode, the apparatus was operated under a nitrogen atmosphere. The first reaction tank was charged with 200 kg / h of a preactivated catalyst having an isopropyl titanate content of 2.0 wt. %, the content of dioctyltin oxide fed from the distillation column, amounting to 5.0 wt. %, and 144 kg / h of N, N-dimethylaminopropylamine (DMAPA). The pre-activation was carried out in an agitated tank at 110 ° C for 2 h. In addition, a circulating backflow leaving the top of the distillation column for separating low-boiling compounds was continuously fed to the first reaction tank through a distillation column (400 kg / h , composition: 70 wt.% of the reagent - methacrylate, as well as methanol, DMAPA and by-products). The molar ratio of MMA: DMAPA in the feed to the reactor was 1.8: 1. In addition, vapors leaving the stirred tank from which methanol was removed in the distillation column was fed to the first reaction tank through the bottom of the column. Under these reaction conditions (pressure of about 500 mbar), the reaction temperature in the first reaction tank was set to 105 ° C. The reaction temperatures in the second and third reaction tanks were 115 and 125 ° C, respectively. The rate of removal of the distillate from the distillation column was 110 kg / h.

The effluent from the first reaction tank was fed to the second reaction tank, and the effluent from the second reaction tank was fed to the third reaction tank. The vapors leaving the separate reaction tanks were continuously fed to the distillation column.

The stream leaving the third reaction tank was continuously fed to a film evaporator located in a column designed to separate low-boiling compounds, in which unreacted DMAPA, methyl methacrylate (MMA) and methanol were removed as a distillate (400 kg / h) and loaded back into the distillation column in the form of a circulating return flow. The bottom product came out of the film evaporator located in the column intended for the separation of low-boiling compounds at a rate of 230 kg / h, and it had the following composition: 98.5 wt. % DMAPMA, <1% low boilers, about 0.5% high boilers, and 130 ppm. N-allyl methacrylamide.

Example 2

Synthesis of DMAPMA in the absence of oxygen

The crude ester was prepared according to example 1.

The vapors leaving the separate reaction tanks were continuously fed to the distillation column.

The stream leaving the third reaction tank was continuously fed to a film evaporator located in a column designed to separate low-boiling compounds, in which unreacted DMAPA, MMA and methanol were removed as a distillate (400 kg / h) and charged back to the distillation column as circulating return flow. The bottom product came out of the film evaporator located in the column intended for the separation of low-boiling compounds at a rate of 230 kg / h, and it had the following composition: 98.3 wt. % DMAPMA, <1% low boilers, about 0.7% high boilers, and 240 ppm. N-allyl methacrylamide.

Comparative example 1

Synthesis of DMAPMA in an oxygen atmosphere

To obtain N, N-dimethylaminopropyl methacrylamide in a continuous mode, 200 kg / h of a preactivated catalyst having an isopropyl titanate content of 2.0 wt. %, the content of dioctyltin oxide fed from the distillation column, amounting to 5.0 wt. %, and 144 kg / h of N, N-dimethylaminopropylamine (DMAPA). The pre-activation was carried out in an agitated tank at 110 ° C for 2 h. In addition, a circulating backflow leaving the top of the distillation column for separating low-boiling compounds was continuously fed to the first reaction tank through a distillation column (400 kg / h , composition: 70 wt.% of the reagent - methacrylate, as well as methanol, DMAPA and by-products). The molar ratio of MMA: DMAPA in the feed to the reactor was 1.8: 1. In addition, vapors leaving the stirred tank from which methanol was removed in the distillation column was fed to the first reaction tank through the bottom of the column. Under these reaction conditions (pressure equal to about 500 mbar), the reaction temperature in the first reaction tank was set to 138 ° C. The reaction temperatures in the second and third reaction tanks were 143 and 155 ° C, respectively. The rate of removal of the distillate from the distillation column was 110 kg / h.

The effluent from the first reaction tank was fed to the second reaction tank, and the effluent from the second reaction tank was fed to the third reaction tank.

The vapors leaving the separate reaction tanks were continuously fed to the distillation column.

The stream leaving the third reaction tank was continuously fed to a film evaporator located in a column designed to separate low-boiling compounds, in which unreacted DMAPA, MMA and methanol were removed as a distillate (400 kg / h) and charged back to the distillation column as circulating return flow. The bottom product came out of the film evaporator located in the column intended for the separation of low-boiling compounds at a rate of 240 kg / h, and it had the following composition: about 90 wt. % DMAPMA, 0.1 wt. % DMAPA, 0.16 wt. % N-allyl methacrylamide, more high-boiling components and trace amounts of reagents.

The crude product was then worked up by a two-stage distillation.

Example 3

Laboratory study of the effect of oxygen on the formation of a compound of formula (IV)

DMAPMA was stabilized using a suitable amount of the described stabilizers and about 10 g of each sample of stabilized DMAPMA was placed in test tubes. Each test tube was equipped with an air or nitrogen inlet. The samples were then heated in different oil baths to temperatures of 110 ° C / 120 ° C / 130 ° C / 140 ° C and 150 ° C, and air or nitrogen was supplied at a gas flow rate of about 0.75 L / h, in each case within 48 hours. The samples were cooled and analyzed by GC (gas chromatography). The contents of N-allyl methacrylamide in DMAPMA are shown in the table below as% GC peak area.

Example 4

Determination of the maximum permissible concentration

Obtaining a copolymer from DMAPMA and N-allyl methacrylamide:

DMAPMA (containing 130 ppm N-allyl methacrylamide) was concentrated by the addition of N-allyl methacrylamide until the total concentration of N-allyl methacrylamide in the mixture was 300 ppm, 400 ppm, 500 ppm. , 600 ppm, 700 ppm, 800 ppm, 1000 ppm and 1200 ppm (N-allyl methacrylamide is available from ABCR, Karlsruhe, Germany, batch: 1300868).

Then 10 g of each sample was initiated by the addition of 0.2% AIBN (azo-bis-isobutyronitrile) and polymerization was carried out in test tubes in a water bath at 70 ° C for 3 hours. The test tubes were cooled to room temperature overnight and then a test tube. A piece of polymer was removed from the solution.

Obtaining aqueous solutions:

The respective polymer pieces were weighed into 125 ml wide-mouth glass bottles and mixed with water to obtain solutions having concentrations equal to 3 or 5%. After 96 h, the completeness of dissolution was checked.

The viscosity of homogeneous solutions was determined after 96 h using a Brookfield viscometer equipped with an adapter for small samples (a meter for low viscosity solutions).

* Viscosity is not determined due to the insolubility of polymers.

Claims (22)

1. A method for producing N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate or their quaternary ammonium salts, wherein said method comprises: interaction in the liquid phase of an alkyl (meth) acrylate with an amine or alcohol to obtain a product containing the specified N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate or their quaternary ammonium salts; where the oxygen concentration in the liquid phase is <1000 ppm, wherein said N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate have formula (I)

, wherein R ₀ denotes hydrogen or methyl, X stands for NH or O, R ₂ denotes a linear, branched or cyclic alkylene radical containing 1-12 carbon atoms, or an aryl radical, which can also be substituted by at least one alkyl group, R ₃ , R _{4 are} all linear, branched or cyclic alkyl radicals containing 1-12 carbon atoms, or an aryl radical, which can also be substituted by at least one alkyl group, and where the product has a content of less than 1200 ppm. compounds of formula (IV)

, in which R ₀ denotes hydrogen or methyl, X stands for NH or O, R ₅ in each case denotes a linear, branched or cyclic alkylene radical, an aryl radical, which can also be substituted by at least one alkyl group, a linear, cyclic or branched alkyl radical containing 1-12 carbon atoms. 2. A method of obtaining N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate according to claim 1 or their quaternary ammonium salts having a compound of formula (IV) of less than 1200 hours / million, which are used to obtain soluble or non-coagulating polymers. 3. A method for producing N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate according to claim 2, having a compound of formula (IV) of less than 1000 ppm. 4. A method for producing N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate according to claim 1, characterized in that the production is carried out in the absence of oxygen. 5. A method for producing N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate according to claim 1, characterized in that the reaction is carried out under a protective gas atmosphere. 6. A method of obtaining N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate according to claim 1, characterized in that the residence time is 0.1-11 hours, preferably 1 -5 hrs 7. A method for producing N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate according to claim 1, characterized in that the reaction is carried out at temperatures between 70 and 160 ° C. 8. A method for producing N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate according to claim 6, characterized in that the reaction is carried out under reduced pressure, preferably in a vacuum. 9. A method for producing N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate according to claim 1, characterized in that alcohol is removed during the reaction. 10. A method of obtaining N, N- (di) alkylaminoalkyl (meth) acrylamide or N, N- (di) alkylaminoalkyl (meth) acrylate according to claim 1, characterized in that inhibitors selected from the group consisting of bis (2- methoxycarbonylpropyl) sulfide, N, N-diethylhydroxylamine, phenothiazine, 4-hydroxy-2,2,6,6-tetramethylpiperidinooxyl or N, N'-diphenyl-p-phenylenediamine or derivatives thereof.